Sorting unit for belt conveyor plants

ABSTRACT

Sorting unit (1) for belt conveyor plants, of the type comprising a first sorting conveyor belt (7) extending between first transmission rollers (11) and revolvingly oscillating around a first oscillation axis (X-Y), extending in parallel and close to one of its longitudinal edges. A second sorting belt (8) is also provided, which extends between second transmission rollers (12) and is placed aside the first sorting belt at the opposite side to the first oscillation axis, as well as revolvingly oscillating around a second oscillation axis (X&#39;-X&#39;) running in parallel and in correspondence of its longitudinal edge placed at the opposite side with respect to the first sorting belt.

BACKGROUND OF THE INVENTION

This invention refers to a sorting unit for belt conveyor plants of thetype comprising a first sorting conveyor belt extending among firsttransmission rollers and revolvingly oscillating around a firstoscillation axis extending in parallel and close to one of itslongitudinal edge, first actuating means to actuate the first sortingbelt and first control means to rotate the first sorting belt around thefirst oscillation axis, bringing it from a rest position, where it layshorizontally, flush with further conveyor belts belonging to saidsorting plant, to a delivery position, where it is transversally slopingand vice versa.

As it is known, belt conveyor plants generally comprise one or more mainconveyor lines consisting of consecutive conveyor belt chains, alongwhich sorting units,which can be singly and selectively operated,areinterposed in order to properly sort the objects transported by the mainconveyor line on different secondary lines.

There are nowadays different kinds of sorting units, each one satisfyingspecific needs, deriving for instance, from the number and thedisposition of secondary conveyor lines on which objects must be sorted.As an example, a known type of sorting unit is basically composed by aflap which oscillates around an horizontal axis, parallel to thelongitudinal development of the main conveyor line. The objects carriedby this conveyor line should selectively fall on a first and on a secondsecondary conveyor line, placed below the main line, depending on theposition of the flap.

Another known type of sorting unit is represented by a conveyor beltplaced downstream a main conveyor line after interposition of a chute.

This conveyor belt extends perpendicularly with respect to thelongitudinal development of the main conveyor line, and can beselectively operated in the opposite direction to deviate the objectsthere conveyed by the chute on secondary conveyor lines, developing inopposite direction, consecutively to the belt itself.

Sorting units, consisting of a conveyor belt extending on thecontinuation of the main conveyor line and revolving on one of its sidesto selectively address the objects to two different secondary conveyorlines, have also been realized. From what has been briefly described,itcan be noted that all sorting units known up to now, originate differentproblems when the corresponding conveyor plant is used to transport andsort, for instance, folded clothings, magazines, or in any case softobjects which shall maintain a predetermined configuration andorientation.

It is easy to imagine, in fact, that a folded blouse or a similararticle of clothing, if not adequately packed up in a rigid box, as itis frequently the case, upsets and rolls itself up when it drops fromthe sorting unit on the secondary conveyor line or, this occurs when theobjects fall from the main conveyor line on the sorting unit, if thesorting unit itself is composed by a conveyor belt which can be operatedin the two directions.

This drawback is due to the fact that in all sorting units known atpresent, the object transported is compelled to drop on the corner onthe secondary conveyor line or on the sorting unit, or to strike againstthe surfaces of these latter with a certain angle.

SUMMARY OF THE INVENTION

Problems similar to the above mentioned one arise when a sorting unitmust send folded clothings or soft objects directly to boxes prearrangedunder it. In this situation the object of this invention is to solve allthe above mentioned drawbacks with a sorting unit by which the objectscoming from a conveyor line can be made opportunely dropped on anotherconveyor line or in a container prearranged downstream the sorting unititself.

Another object of the present invention is that this sorting unit caneasily be aligned with sorting units of the same kind to form multiplesorting stations.

All but last object of this invention is that this sorting unit caneasily be realized in the sector industry.

These objects, and others still, which will become more apparenthereinafter, are basically attained by a sorting unit for belt conveyorplants, of the type comprising a first sorting conveyor belt extendingamong first transmission rollers and revolving around a firstoscillation axis extending in parallel and close to one of itslongitudinal edge, first actuating means to actuate the first sortingbelt, first control means to rotate the first sorting belt around thefirst oscillation axis bringing it from a rest position, in which itlays horizontally flush with other conveyor belts being part of saidsorting plant, to a delivery position where it is transversally slopingand viceversa, characterized by the fact that it comprises a secondsorting belt extending among second transmission rollers and placedaside the first sorting belt at the opposite side of the firstoscillation axis, as well as revolvingly oscillating around a secondoscillation axis extending in parallel and in correspondence of itslongitudinal edge positioned at the opposite side with respect to thefirst sorting belt, second actuating means to actuate said secondsorting belt in the same direction and at the same speed of the firstsorting belt and second control means to rotate the second sorting beltaround the second oscillation axis bringing it from a rest position, inwhich it lays horizontally flush with said further conveyor belts, to adelivery position, in which it is transversally sloping, and viceversa,said first and second control means simultaneously operating onrespective sorting belts, these latter being symetrically aligned withrespect to further conveyor belts.

BRIEF DISCRIPTION OF THE DRAWINGS

Further characteristics and advantages shall better appear from thedetailed description of a preferred, but not exclusive, embodiment of asorting device for belt conveyor plants according to this invention,made hereinafter with reference to the accompanying drawings, given forindicative and not exclusive purposes, in which:

FIG. 1 shows a schematic and interrupted plan view of a conveyor plantprovided with a sorting unit according to the invention.

FIG. 2 shows a top view of the subject sorting unit.

FIG. 3 is a frontal view of the sorting unit.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the above mentioned figures, 1 indicates as a whole asorting unit for belt conveyor plants, according to the presentinvention.

As it appears from FIG. 1, the sorting unit 1 is part of a belt conveyorplant marked 2, and it can be interposed between a main conveyor line 3and two secondary conveyor lines. More in particular the sorting unit 1operates, as it will be better clarified hereinafter, in such a way asto send the objects coming from the main conveyor line 3, in a selectiveway, to a first secondary conveyor line 4, extending in line andcoplanar with the main line 3, or on a second secondary conveyor line 5extending according to a plan placed below the main conveyor line 3.

The number and the disposition of the secondary conveyor lines is notrelevant for the objects of the present invention. In fact, as itappears from FIG. 3, it can be foreseen that instead of the secondsecondary conveyor line 5, a packing box 6 or the like be prearrangedunder the sorting unit 1, in such a way that this latter can make theobjects coming from the main line 3 dropped directly into the same.

Originally, according to this invention the sorting unit 1 includes afirst sorting conveyor belt 7 and a second sorting conveyor belt 8, oneat the side of the other and symetrically extending in line with furtherconveyor belts 9 and 10, presented respectively by the main conveyorline 3 and by the first secondary conveyor line 4.

Preferably it is foreseen that the sum of widths of the sorting belts 7and 8 is equal to the widths of conveyor belts 9 and 10.

As it is known, the sorting belts 7 and 8 are composed by a plurality ofbelt elements 7A and 8A extending, respectively, between first andsecond transmission rollers 11 and 12.

The sorting belts 7 and 8 are furthermore oscillating according to afirst and a second oscillation axis X--X and X'--X' respectively,extending in parallel and in correspondence of the opposite edges of thesame, to be brought, as it shall be better clarified hereinafter, from arest position in which they are horizontally positioned in line withfurther conveyor belts 9 and 10, to a discharge position where, asindicated with a dotted line in FIG. 3, they are transversally tilteddownward to let the carried objects drop into box 6 or on the secondaryconveyor line 5.

In addition, first and second operation means 13 and 14 are foreseenwhich operate on the first sorting belt 7 and on the second sorting belt8 respectively, as to give, through one of the transmission rollers 11and 12, a conventional translatory conveying motion in the samedirection to the belts.

Originally, the operation means 13 and 14 are made each one of anoperation shaft 15 extending in parallel to the longitudinal developmentof the respective sorting belt 7 or 8, adjacent to its farest side withrespect to the other sorting belt. To this purpose, each operating shaft15 is revolvingly supported, with respect to a fixed structure 16, bysupporting elements 17 clamped to the fixed structure itself. Inpreference it is foreseen that each operation shaft 15 is operated inrotation in the direction of the rotation made by the relevant sortingbelt 7 or 8 when this latter is brought from the rest position to thedischarge position, for the purposes which will better appearhereinafter.

The rotary motion of the operation shafts 15 can be obtained throughtransmission gears which can be associated to each one of the shafts incorrespondence of half part of the flexible coupling 18 and 19 placedrespectively at the opposite ends of these latter. These transmissionmembers can be operated both by an engine associated to the sortingmodule 1 and by the main 3 or secondary 4 conveyor lines. Both thetransmission members and the engine, mentioned above have not beenillustrated and they will no more be described as known per se andconventional and in any case not decisive with a view to the presentinvention.

To advantage, the half-parts of flexible couplings 18 and 19 allow alsothe motion transmission among the operation shafts of several sortingunits 1 when these are aligned in sequence in order to sort the objectson several secondary lines or in different containing boxes.

Each one of the operation shafts 15 revolvingly supports a couple ofconnection elements 20 each one of which, in its turn revolvinglysupports one of the transmission rollers 11 or 12 at one of its ends.

Two bars 21 revolvingly engage the transmission rollers 11 and thetransmission rollers 12 respectively, from the opposite side at theirends engaged by the connection elements 20.

Each operation shaft 15 transmits the motion to the relevant sortingbelt 7 or 8 through at least a couple of conic gears 22 and 23respectively keyed on the shaft 15 and on one of the transmissionrollers 11 and 12. As it can be noticed from FIGS. 2 and 3, it ispreferably foreseen that connection elements 20 have a box-shapedconfiguration, in such a way that gears 22 and 23 can be accomodatedinside the same.

To the sorting belts 7 and 8 are furthermore associated the first andsecond control means 24 and 25 respectively, simultaneously operating soas to bring the relevant sorting belts 7 and 8 from the rest to thedelivery position and viceversa.

In a preferred embodiment it is foreseen that these control meansinclude each one at least a fluid-dynamic cylinder 26 engaged to thefixed structure 16 and operating on one of the connection elements 20.In the case shown, two of these fluid-dynamic cylinders 26 each oneoperating on the relevant connection elements 20 are foreseen on eachsorting belt 7 and 8. If it were foreseen only one fluid-dynamiccylinder 26 for each sorting belt, connection elements 20 must berigidly connected one to each other so as to be simultaneously operatedby the fluid-dynamic cylinder 26.

After what has been described in a mainly structural meaning, theoperation of the sorting unit according to the invention is thefollowing. When in rest position, sorting belts 7 and 8, operated by therelevant operation shafts 15, form a continuous surface with theconveyor belts 9 and 10, in such a way that the objects coming from themain conveyor line 3 can be brought on the first secondary conveyor line4.

The positioning of the sorting belts 7 and 8 with respect to the mainconveyor line 3 is arranged in such a way that the objects carried alongthe sorting unit 1 result supported by both belts 7 and 8 substantiallyby two symetrically opposed portions. This situation is clearly shown inFIG. 3 in which one of these objects has been represented with a dottedline and marked with number 27.

When the object 27 translating on the sorting unit 1 is to be madedropped on the second secondary conveyor line 5 or in the box 6,fluid-dynamic cylinders 26 are simultaneously operated by known andconventional means.

These ones, acting on connection elements 20, force sorting belts 7 and8 to rotate downward around the axis of the relevant operation shafts15, which represent the first and the second oscillation axis X--X andX'--X', respectively. By this rotation, belts 7 and 8 take the deliveryposition and the object 27 is therefore subject to drop on the secondaryconveyor line 5 or in the box 6, as shown in FIG. 3.

To advantage, as it easy to think, the immediate and simultaneouslowering of the surfaces carrying the object 27 allows that thismaintains a substantially horizontal oritentation during its free fall.

In this way, even if the object is for instance an article of clothingor in any case an easily deformable element it is not subject to getupset or to curl up upon the impact with the surface under the sortingunit.

This effect is reached thanks to the motion transmission through gears22 and 23, belts 7 and 8 are subject to slow down the carrying speed ofthe object 27 when they are brought from the rest position to thedischarge position.

This speed can even be nullified acting in such a way that fluid-dynamiccylinders 26 give to the relevant sorting belts 7 and 8 an angularvelocity equal to that of the operation shafts 15.

Immediately after that the object 27 has dropped, sorting belts 7 and 8are automatically brought again, always through the fluid-dynamiccylinders 26, in the rest position to receive a new object from the mainconveyor line 3.

This invention so attains the proposed objects. As it appears from whatabove stated, the subject sorting unit operates in such a way as to makethe object dropped in the fittest way as to avoid, at the moment of theimpact, impact forces localized on certain points of the object itself,which would tend to cause a deformation of the same. This makes thesorting module 1 adequate to sort also soft objects; this could not beobtained in a satisfactory way with the utilization of sorting units ofthe known type.

The subject sorting unit is furthermore easy to carry out by the sectorindustry and shows a high utilization versatility since it can easily beapplied to conveyor plants of any type. Naturally, a number ofmodifications and variations can be made to this invention, withoutleaving the inventive concept characterizing it.

For example, the operation shafts and the gears can be replaced byconventional belt and pulley transmission usually employed in conveyorplants. In this case, it would be waved the advantage to obtain aslowing down or evenly a cancellation of the object transport speed whensorting belts are brough from the rest position to the delivery one.Fuild-dynamic cylinders 26 can furthermore be replaced, e.g. by couplingjoints installed on the operation shafts 15 and operating in such a wayas to make the connection elements 20 temporarily integral with theshafts to obtain the lowering in the sorting belts 7 and 8.

We claim:
 1. A sorting unit for belt conveyor plants, of the typecomprising a first sorting conveyor belt extending among firsttransmission rollers and revolvingly oscillating around a firstoscillation axis, said axis extending in parallel and close to alongitudinal edge of said first sorting belt, first actuating means toactuate the first sorting belt during at least a part of a sortingoperation and oscillation axis, bringing it from a rest position, whereit lays horizontally flush with other conveyor belts being part of saidsorting plant, to a delivery position where it is inclined with respectto said other conveyor belts, and vice versa, characterized in that saidsorting unit comprises a second sorting belt extending among secondtransmission rollers and placed adjacent the first sorting belt at aside thereof opposite said longitudinal edge of said first sorting belt,as well as revolvingly oscillating around a second oscillation axisrunning in parallel and close to a longitudinal edge of said secondsorting belt opposite the first sorting belt, second actuating means toactuate said second sorting belt in the same direction and at the samespeed as the first sorting belt during said part of a sorting operation,and second control means to rotate the second sorting belt around thesecond oscillation axis bringing it from a rest position in which it ishorizontally flush with said other conveyor belts, to a deliveryposition in which it is inclined with respect to said other conveyorbelts, and vice versa, said first and second control meanssimultaneously operating on the relevant sorting belts during said partof said sorting operation, these latter being symmetrically aligned inrespect with further conveyor belts.
 2. A sorting unit according toclaim 1, characterized in that said sorting belts are transversallytilted downward when in their delivery position.
 3. A sorting unitaccording to claim 1, characterized in that said actuating meanscomprise for each one of said sorting belts, at least one operationshaft activated in rotation, revolvingly supported with respect to afixed structure, and having its own axis coinciding with the oscillationaxis of the respective sorting belt, at least a couple of conic gearskeyed, respectively, on the corresponding operation shaft and on one ofsaid transmission rollers, as well as operatively engaged with eachother, and at least two connection elements revolvingly engaged on therelevant operation shaft, each one of said elements revolvingly engaginga transmission roller of the corresponding sorting belt.
 4. A sortingunit according to claim 3, characterized in that said control meansinclude, for each one of said sorting conveyor belts, at least twofluid-dynamic cylinders engaged on said fixed structure and operatingeach on one of said connection elements.
 5. A sorting unit according toclaim 3, characterized in that said control means include, for each oneof said sorting belts, a fluid-dynamic cylinder engaged on said fixedstructure and operating on one of said connection elements, the latterbeing rigidly engaged with each other.
 6. A sorting unit according toclaim 3, characterized in that each one of said operation shafts rotatesin the direction of rotation of the relevant sorting belt when thislatter is brought from the rest position to the delivery position by therespective control means.
 7. A sorting unit according to claim 6,characterized in that said control means make the respective sortingbelt rotate around the corresponding oscillation axis at an angularvelocity equal that of said operation shaft.
 8. A sorting unit accordingto claim 3, characterized in that each one of said operation shafts isequipped with at least two half-parts of flexible couplings supported onits opposed ends.
 9. A sorting unit according to claim 1, characterizedin that the sum of widths of said sorting belts is substantially equalto the width of said other conveyor belts.
 10. A sorting unit accordingto claim 3, characterized in that said control means include, for eachone of said sorting conveyor belts, at least two fluid-dynamic cylindersengaged on said fixed structure and operating each on one of saidconnection elements.
 11. A sorting unit according to claim 3,characterized in that said control means include, for each one of saidsorting belts, a fluid-dynamic cylinder engaged on said fixed structureand operating on one of said connection elements, the latter beingrigidly engaged with each other.
 12. A sorting unit according to claim3, characterized in that each one of said operating shafts rotates inthe direction of rotation of the relevant sorting belt when this latteris brought from the rest position to the delivery position by therespective control means.